only about 100,000 people in the u.s. suffer from it. the device could be used to treat millions who can't see. >> i think that the future for this is going to be big. >> reporter: let's hope. and if you're wondering what sparked the doctor's interest in blindness? it turns out, his grandmother went blind. so, he devoted his entire career to finding a cure for this. >> how rewarding for him. >> thanks, gio. appreciate it. >>> coming up on the broadcast, not only will we show you the sloth on the speedboat. the big question for "star wars" geeks. is harrison ford going to go solo one more time? keep it here. how can you get back pain relief that lasts up to 16 hours? with thermacare heatwraps. thermacare works differently. it's the only wrap with patented heat cells that penetrate deep to relax, soothe, and unlock tight muscles. for up to 16 hours of relief, try thermacare. ♪ ♪ "love" a collection by prabal gurung, exclusively at target. for a limited time. now you can help too. when you buy a bag of pedigree, you'll help more shelter